diff --git a/internal/handler/metrics.go b/internal/handler/metrics.go
index ea58e49..ff21821 100644
--- a/internal/handler/metrics.go
+++ b/internal/handler/metrics.go
@@ -161,30 +161,54 @@ func (h *ProxyHandler) MetricsHandler(w http.ResponseWriter, r *http.Request) {
 	metrics.LatencyStats.Max = utils.SafeString(latencyStats["max"], "0ms")
 
 	// 处理分布数据
+	log.Printf("[MetricsHandler] 处理延迟分布数据: stats[latency_stats]=%v", stats["latency_stats"])
+
 	if stats["latency_stats"] != nil {
-		if distribution, ok := stats["latency_stats"].(map[string]interface{})["distribution"]; ok && distribution != nil {
-			if distributionMap, ok := distribution.(map[string]interface{}); ok {
-				metrics.LatencyStats.Distribution = make(map[string]int64)
-				for k, v := range distributionMap {
-					if intValue, ok := v.(float64); ok {
-						metrics.LatencyStats.Distribution[k] = int64(intValue)
-					} else if intValue, ok := v.(int64); ok {
-						metrics.LatencyStats.Distribution[k] = intValue
+		latencyStatsMap, ok := stats["latency_stats"].(map[string]interface{})
+		if ok {
+			log.Printf("[MetricsHandler] latencyStatsMap=%v", latencyStatsMap)
+			distribution, ok := latencyStatsMap["distribution"]
+			if ok && distribution != nil {
+				log.Printf("[MetricsHandler] distribution=%v", distribution)
+				distributionMap, ok := distribution.(map[string]interface{})
+				if ok {
+					log.Printf("[MetricsHandler] distributionMap=%v", distributionMap)
+					metrics.LatencyStats.Distribution = make(map[string]int64)
+					for k, v := range distributionMap {
+						log.Printf("[MetricsHandler] 处理延迟分布项: %s=%v (type=%T)", k, v, v)
+						if intValue, ok := v.(float64); ok {
+							metrics.LatencyStats.Distribution[k] = int64(intValue)
+							log.Printf("[MetricsHandler] 转换为int64: %s=%d", k, int64(intValue))
+						} else if intValue, ok := v.(int64); ok {
+							metrics.LatencyStats.Distribution[k] = intValue
+							log.Printf("[MetricsHandler] 已经是int64: %s=%d", k, intValue)
+						} else {
+							log.Printf("[MetricsHandler] 无法转换: %s=%v (type=%T)", k, v, v)
+						}
 					}
+				} else {
+					log.Printf("[MetricsHandler] distribution不是map: %v (type=%T)", distribution, distribution)
 				}
+			} else {
+				log.Printf("[MetricsHandler] 没有distribution字段或为nil: ok=%v, distribution=%v", ok, distribution)
 			}
+		} else {
+			log.Printf("[MetricsHandler] latency_stats不是map: %v (type=%T)", stats["latency_stats"], stats["latency_stats"])
 		}
+	} else {
+		log.Printf("[MetricsHandler] latency_stats为nil")
 	}
 
 	// 如果分布数据为空，初始化一个空的分布
 	if metrics.LatencyStats.Distribution == nil {
+		log.Printf("[MetricsHandler] 初始化空的延迟分布")
 		metrics.LatencyStats.Distribution = make(map[string]int64)
 		// 添加默认的延迟桶
-		metrics.LatencyStats.Distribution["<10ms"] = 0
+		metrics.LatencyStats.Distribution["lt10ms"] = 0
 		metrics.LatencyStats.Distribution["10-50ms"] = 0
 		metrics.LatencyStats.Distribution["50-200ms"] = 0
 		metrics.LatencyStats.Distribution["200-1000ms"] = 0
-		metrics.LatencyStats.Distribution[">1s"] = 0
+		metrics.LatencyStats.Distribution["gt1s"] = 0
 	}
 
 	// 填充错误统计数据
diff --git a/internal/metrics/collector.go b/internal/metrics/collector.go
index 5efa491..31d772d 100644
--- a/internal/metrics/collector.go
+++ b/internal/metrics/collector.go
@@ -61,7 +61,7 @@ func InitCollector(cfg *config.Config) error {
 		instance.bandwidthStats.history = make(map[string]int64)
 
 		// 初始化延迟分布桶
-		buckets := []string{"<10ms", "10-50ms", "50-200ms", "200-1000ms", ">1s"}
+		buckets := []string{"lt10ms", "10-50ms", "50-200ms", "200-1000ms", "gt1s"}
 		for _, bucket := range buckets {
 			counter := new(int64)
 			*counter = 0
@@ -132,7 +132,7 @@ func (c *Collector) RecordRequest(path string, status int, latency time.Duration
 	var bucketKey string
 	switch {
 	case latencyMs < 10:
-		bucketKey = "<10ms"
+		bucketKey = "lt10ms"
 	case latencyMs < 50:
 		bucketKey = "10-50ms"
 	case latencyMs < 200:
@@ -140,14 +140,20 @@ func (c *Collector) RecordRequest(path string, status int, latency time.Duration
 	case latencyMs < 1000:
 		bucketKey = "200-1000ms"
 	default:
-		bucketKey = ">1s"
+		bucketKey = "gt1s"
 	}
+
+	log.Printf("[Metrics] 更新延迟分布: 路径=%s, 延迟=%dms, 桶=%s", path, latencyMs, bucketKey)
+
 	if counter, ok := c.latencyBuckets.Load(bucketKey); ok {
-		atomic.AddInt64(counter.(*int64), 1)
+		oldValue := atomic.LoadInt64(counter.(*int64))
+		newValue := atomic.AddInt64(counter.(*int64), 1)
+		log.Printf("[Metrics] 延迟分布桶 %s: %d -> %d", bucketKey, oldValue, newValue)
 	} else {
 		counter := new(int64)
 		*counter = 1
 		c.latencyBuckets.Store(bucketKey, counter)
+		log.Printf("[Metrics] 新建延迟分布桶: %s = 1", bucketKey)
 	}
 
 	// 更新路径统计
@@ -347,19 +353,25 @@ func (c *Collector) GetStats() map[string]interface{} {
 	latencyDistribution := make(map[string]int64)
 
 	// 确保所有桶都存在，即使计数为0
-	buckets := []string{"<10ms", "10-50ms", "50-200ms", "200-1000ms", ">1s"}
+	buckets := []string{"lt10ms", "10-50ms", "50-200ms", "200-1000ms", "gt1s"}
 	for _, bucket := range buckets {
 		if counter, ok := c.latencyBuckets.Load(bucket); ok {
 			if counter != nil {
-				latencyDistribution[bucket] = atomic.LoadInt64(counter.(*int64))
+				value := atomic.LoadInt64(counter.(*int64))
+				latencyDistribution[bucket] = value
+				log.Printf("[Metrics] 延迟分布桶 %s = %d", bucket, value)
 			} else {
 				latencyDistribution[bucket] = 0
+				log.Printf("[Metrics] 延迟分布桶 %s = 0 (counter is nil)", bucket)
 			}
 		} else {
 			latencyDistribution[bucket] = 0
+			log.Printf("[Metrics] 延迟分布桶 %s = 0 (bucket not found)", bucket)
 		}
 	}
 
+	log.Printf("[Metrics] 延迟分布: %v", latencyDistribution)
+
 	// 获取最近请求记录（使用读锁）
 	recentRequests := c.recentRequests.GetAll()
 
diff --git a/web/app/dashboard/page.tsx b/web/app/dashboard/page.tsx
index c0babf7..0156213 100644
--- a/web/app/dashboard/page.tsx
+++ b/web/app/dashboard/page.tsx
@@ -266,21 +266,27 @@ export default function DashboardPage() {
                     Object.entries(metrics.latency_stats.distribution)
                       .sort((a, b) => {
                         // 按照延迟范围排序
-                        const order = ["<10ms", "10-50ms", "50-200ms", "200-1000ms", ">1s"];
+                        const order = ["lt10ms", "10-50ms", "50-200ms", "200-1000ms", "gt1s"];
                         return order.indexOf(a[0]) - order.indexOf(b[0]);
                       })
-                      .map(([range, count]) => (
-                        <div key={range} className="p-3 rounded-lg border bg-card text-card-foreground shadow-sm">
-                          <div className="text-sm font-medium text-gray-500">{range}</div>
-                          <div className="text-lg font-semibold">{count}</div>
-                          <div className="text-xs text-gray-500 mt-1">
-                            {Object.values(metrics.latency_stats?.distribution || {}).reduce((sum, val) => sum + val, 0) > 0
-                              ? ((count / Object.values(metrics.latency_stats?.distribution || {}).reduce((sum, val) => sum + val, 0)) * 100).toFixed(1)
-                              : 0}%
+                      .map(([range, count]) => {
+                        // 转换桶键为更友好的显示
+                        let displayRange = range;
+                        if (range === "lt10ms") displayRange = "<10ms";
+                        if (range === "gt1s") displayRange = ">1s";
+                        
+                        return (
+                          <div key={range} className="p-3 rounded-lg border bg-card text-card-foreground shadow-sm">
+                            <div className="text-sm font-medium text-gray-500">{displayRange}</div>
+                            <div className="text-lg font-semibold">{count}</div>
+                            <div className="text-xs text-gray-500 mt-1">
+                              {Object.values(metrics.latency_stats?.distribution || {}).reduce((sum, val) => sum + val, 0) > 0
+                                ? ((count / Object.values(metrics.latency_stats?.distribution || {}).reduce((sum, val) => sum + val, 0)) * 100).toFixed(1)
+                                : 0}%
+                            </div>
                           </div>
-                        </div>
-                      ))
-                  }
+                        );
+                      })}
                 </div>
               </div>
             </div>